Gastroenterology
Pendik Medipol University Hospital
1999 Karadeniz Technical University, Gastroenterology
1997 Atatürk University, Internal Diseases Professorship
1992 Atatürk University, Internal Diseases Associated Professorship
1985 Atatürk University, Internal Diseases Specialist
1981 Atatürk University Faculty of Medicine
1- Nihat Okçu Gülçin Polat, Arif Yılmaz, Mehmet Koruk, The demographic features of gastric cancers in Erzurum(Eurasian J Med 2000; 32: 63-65)
2- An Evaluation of Upper Gastrointestinal Bleeding Cases. Clinical Sciences-Doctor.2000, - E.akarsu,N.Okçu,et Ark.Northeast Anatolia 6:4:435-438
3-N.Okçu, A.yılmaz. İ.kiki,MDonuk, C.gündoğdu, H.uzunismail. Our Diagnostic Upper Gastrointestinal Endoscopy Results. Atatürk University Medical Journal 1997,29 (2):486
4-N. Okçu, M.gündoğdu, MD onuk, İ.kiki, l.cerrahoğlu, k.yılmaz, I. çapoğlu. The Role of Misoprostol in Preventing Gastroduodenal Lesions in Patients Using Nonsteroidal Anti-Inflammatory Drugs (NSAIDs). Atatürk University Medical Journal 1997,29 (2):453-455.
5-N.Okçu, A. Öz, MD Onuk, E.Akarsu, B. Tekin, Hz Tonbul, H.Kaya. Plasma Fibronectin Levels in Chronic Active Hepatitis and Decoction of Liver Parenchymal Insufficiency and Their Relationship with Liver Functional Status. Turkish J. Gastroenterol 1995;27(4): 422-426.
6-N.Okçu, Tahir Buran, MD Onuk, A. Yılmaz, E.Akarsu, G. Akçay. Prevalence of Helicobacter Pylori in Patients with Duodenal Ulcer in Erzurum and Surrounding Area. Turkish J. Gastroenterol 1995;27(4): 447-450.
7-N.Okçu, bs awake, e. akarsu, e. bakan, z. tonbul. Importance of Carbohydrate Antigens (CA-19-9, CA-125), Carcinoembryonic Antigen (CEA) and Alkaline Phosphatase in Gastric and Colorectal Cancers. Turkish J. Gastroenterol 1995;6:467-471.
8-N. Okçu, MD Onuk, E. Akarsu, H. Doğan, C. Gündoğdu. Major Risk Factors in Patients with Hepatocellular Carcinoma in Our Region. Gastroenterology 1994;5(2):154-157
9-N.Okçu, md. Onuk, e. akarsu, h. doğan, c.gündoğdu, tahir buran. Frequency of gastric carcinoma in Erzurum region, endoscopic and histological features. Gastroenterology 1994;5(2):263-267.
10-N. Okçu, MD Onuk, Tahir Buran, E. Akarsu, MA Çiftçioğlu. Frequency of Helicobacter Pylori in Nonspecific Gastritis Cases in Erzurum Province. Gastroenterology 1994;5(2):211-213.
11-N.Okçu, MD Onuk, Ö. Ünal, E. Akarsu, L. İncesu, K. Akgöz. Diagnostic Value of Ultrasound-Guided Fine Needle Aspiration Biopsy in Intra-Abdominal Mass Lesions. Gastroenterology 1993;4(1):166-68.
12-NOkçu, md. onuk, m. polat, a. yılmaz, m. gündoğdu, m. paç. Budd-Chiari Syndrome (2 Cases). Turkish J Gastroenterhepatol 1993; 4(1):77-80.
13-N.Okçu, H. Koçak, MD Onuk, M. Gündoğdu, E. Bakan, A. Yılmaz, A. Başoğlu, A. Ateş, F.A. Paç. The Effect of Atrial Pressure Changes and Cardiac Nerves on Plasma Atrial Natriuretic Peptide (ANP) Levels. Vascular Surgery 1993; 27(2): 128-132
15-N.Okçu, MD Onuk, A.Yılmaz, M. Gündoğdu, T. Buran. Effects of Omeprozole and Ranitidine on Peptic Ulcer Healing. Doğa-Tr.J. of Medical Sciences 1992;16:657-658.
16-N. Okçu, Mr. Yiğitoğlu, B. Adam, E. Bakan. The Effect of Digixin on Plasma Atrial Natriuretic Peptic Level in Patients with Congestive Heart Failure. S.Ü. Medical Faculty Journal 1991;7(2):243-247..
17-N.Okçu, A. Yılmaz. The Effect of Histamine H2 -Receptor Antagonists in Upper Gastrointestinal System Bleeding. Endoscopy Journal 1991;2(4):17-23.
18-N.Okçu, E. Bakan, B. Adam, A. Yılmaz, Mr. Yiğitoğlu. Sex Hormones and Sex Hormone Binding Globulin Levels in Patients with Chronic Hepatitis and Liver Cirrhosis (Letter to the Editor). Nature-Tr. J. Of Medical Sciences 1991;15:1-2.
19-N.Okcu Ömer Yılmaz.Helıcobacter pylori and related gastrointestinal system diseases. Turkish Clinics JMed Sci. 2013;33(3):806-13
20-Nihat Okçu, Ömer Yılmaz, Hakan Dursun, Gülçin Polat. The relationship between dyspeptic symptoms, nutritional habits, endoscopic and histological findings (Eurasian J Med 2006; 38: 13-17)
21-Mehmet Bilici,1Nihat Okcu,1Kerim Cayir,1Ibrahim Pirim,2Salim B. Tekin,1andCemal Gundogdu3 - Distribution of HLA Tissue Groups in Patients with Gastric Cancer Eurasian J Med. 2010 Apr; 42(1): 9.11.
22-Nihat Okcu,Abdulhalim Bak,Mehmet Sari,Mehmet Arslan,Sait Kapicioglu:The fibroblast proliferation, relationship of hepatocyte growth factor (HGF) and interferon-A2A Gastroenterology April 2000Volume 118,Issue 4, Part 2, PageA1404
23-Kubra Kaynar,Sait Kapicioglu,Mehmet Sari,Nihat Okcu,Abdulhalim Baki. The effect of fish oil on stress ulcer prophylaxis GastroenterologyVolume 118, Issue 4, Part 2, PageA1255
Dr. Tülin Kendir Koçak is a board-certified gastroenterologist and internal medicine specialist. She has over 25 years of clinical experience. Dr. Koçak is skilled in advanced endoscopic procedures such as esophagogastroduodenoscopy, colonoscopy, chromoendoscopy, and flexible rectosigmoidoscopy. She has performed many specialized interventions, including esophageal variceal band ligation, achalasia balloon dilatation, polypectomy, foreign body removal, and percutaneous endoscopic gastrostomy (PEG).
Dr. Koçak graduated from Istanbul University Cerrahpasa Faculty of Medicine. She completed her advanced training at leading hospitals in Turkey. She has held important roles in both public and private healthcare institutions. Dr. Koçak’s extensive hands-on experience makes her a respected expert in gastroenterology.
Dr. Ozden Gul is a general surgeon trained at Istanbul University Cerrahpaşa Faculty of Medicine. She completed her general surgery residency at Haydarpaşa Numune Training and Research Hospital. She has decades of surgical experience and is fluent in English.
Her practice includes gastrointestinal surgery (gallbladder disease, hernias, appendicitis, GI disorders). She also treats endocrine conditions (thyroid, parathyroid, adrenal) and breast disease, both benign and malignant. She manages emergency and trauma cases. She offers minimally invasive laparoscopic surgery.
She has worked at Haydarpaşa Numune, Bakırköy, Taksim First Aid, Uzunköprü State, Keşan State, Beykoz Medical Center, and Medivia Hospital. She is known for meticulous technique and patient-centered care.
Dr. Abu Shamsiya Rami Nuamanovych is a specialist in general and laparoscopic surgery, oncology, and ultrasound diagnostics. He is a Candidate of Medical Sciences, an associate professor, and a doctor of the highest category. Dr. Nuamanovych is a member of the Ukrainian Association of Bariatric Surgeons and the World Organization of Bariatric Surgeons (IFSO).
He works as a WHO consultant on laparoscopic surgery. He is also President of the Association of Arab Doctors of Ukraine. Dr. Nuamanovych has performed thousands of surgeries, including hernia repairs, bariatric procedures, and cancer operations. His skills are recognized internationally. He speaks English and Arabic fluently.
准教授アリ・ソルマズ博士は、20年以上の経験を持つ一般外科および肥満外科専門医です。一般外科、代謝外科、肥満外科を専門としています。トルコ有数の高等教育機関であるマルマラ大学にて医学教育および外科研修を修了しました。准教授の称号はバージュラル教育研究病院にて取得しました。
ソルマズ博士は、チャムルジャ・エルデム病院およびバージュラル教育研究病院をはじめとする複数の医療機関において、数千件の手術を執刀してきました。腹腔鏡手術および低侵襲外科の分野において高い技術を有しており、患者の早期回復と良好な治療成績に貢献しています。
積極的に学術研究活動に従事しており、複数の学術誌の編集委員会に参加しています。IFSO（国際肥満・代謝外科連盟）、トルコ外科学会、および肥満代謝外科学会を含む専門職業団体の会員です。
Dr. Osman Aktas has been serving as a general surgeon at Ataşehir Avicenna Hospital since 2005. Born in Kayseri in 1960, he graduated with his medical degree from Ankara University in 1983. Following his graduation, he fulfilled his military service in medical units for two years. He completed his general surgery residency at GATA from 1986 to 1990. After specializing in general surgery, He held key positions as head of general surgery departments and chief physician in several prominent military hospitals, including Tatvan, Diyarbakır, Ankara, and Manisa.
Dr. Osman has had a special focus on endoscopic surgery since 1995. He received advanced training in laparoscopic surgery techniques in Germany and has successfully performed a wide range of laparoscopic procedures. His expertise extends to gallbladder surgery, abdominal wall and inguinal hernia repairs, appendicitis, reflux and stomach surgeries, as well as complex cases such as gastrointestinal tumors, intestinal obstructions, and various other intestinal diseases, all managed through minimally invasive methods.
In 2002, Dr. Osman transitioned to the private sector, where he broadened his practice to include modern treatments for anal diseases like hemorrhoids, fistulas, and fissures, utilizing advanced techniques such as laser therapy.
Dr. Osman is also recognized for his significant contributions to oncological surgery. He has a wealth of experience in the surgical treatment of various cancers, including breast and thyroid cancer, where he has implemented new treatment methods that reduce the risk of complications. His surgical expertise spans critical cancer surgeries, such as the Whipple procedure for pancreatic cancer, colorectal cancer resections, gastric cancer, and other complex malignancies. Additionally, his skills in metabolic surgery have led to lasting outcomes for patients suffering from obesity and diabetes, ensuring a better quality of life through sustained weight loss and reduced risk of diabetes.
With his vast experience and advanced skills in both laparoscopic and cancer surgeries, Dr. Osman remains at the forefront of surgical excellence, offering innovative and comprehensive care to all his patients.
Education
Experience
Professional Memberships
TTB-Istanbul Medical Chamber
Turkish Surgery Association
Turkish Colon and Rectum Surgery Association
Turkish Hepato-Pancreato-Biliary Surgery Association
Procedures Performed
Dr. Eda Tereh Akay is a general surgeon. She completed specialty training in general surgery and provides patient-centered care with modern techniques.
Her expertise includes gastrointestinal surgery (gallbladder, hernias, appendicitis, gastrointestinal tract disorders), endocrine surgery (thyroid, parathyroid, adrenal), breast surgery (benign and malignant), minimally invasive laparoscopic procedures, and emergency and trauma surgery. She is known for precise surgical skills and a strong focus on patient safety.
Dr. Specialist Surgeon Rafail Ibayev is an expert in advanced gastrointestinal surgery. He specializes in both laparoscopic and open procedures for diseases of the stomach, intestine, and rectum. Dr. Ibayev is a recognized leader in obesity and metabolic surgery. He has extensive experience in sleeve gastrectomy, gastric bypass, and gastric balloon procedures. His patients achieve high success rates in weight management and metabolic health.
Dr. Ibayev is known for his work in minimally invasive surgery. He performs a wide range of laparoscopic operations that help patients recover faster and with less scarring. He is also skilled in endocrine and breast surgery, including advanced oncoplastic techniques for both benign and malignant conditions. As a gastrointestinal cancer specialist, he performs complex surgeries for liver, stomach, and colorectal tumors. He provides modern and effective oncological care.
Dr. Ibayev is highly trained in anti-reflux surgery, treatment of digestive disorders, endoscopic procedures, hernia repair, splenectomy, and proctologic surgeries. He is committed to patient-centered care and long-term health outcomes.
Dr. Jumana Baryhe is a specialist in advanced aesthetic and hair restoration procedures. She performs Botox injections, non-surgical nose correction, FUE and DHI hair transplants, beard and eyebrow transplants, brow lifts, lip implants, and laser vaginal rejuvenation. Dr. Baryhe is known for her skill in minimally invasive techniques. Her patients report high satisfaction with their results.
Dr. Baryhe is dedicated to excellence in her field. She has completed hundreds of successful procedures. Her reputation is built on technical expertise and personalized care. She uses the latest methods and follows international standards in cosmetic medicine.
Dr. Murat Erol is a general dentist with over 20 years of clinical experience. He graduated from Ege University Faculty of Dentistry in 2002. He provides care in English.
He offers preventive care and restorative treatments, including aesthetic fillings, crowns, and bridges. He also performs root canal therapy. His aesthetic services include whitening, composite bonding, and smile design. He provides fixed and removable prosthetics. His plans focus on oral function and natural aesthetics. Each treatment is tailored to the patient.
Dr. Jaydeep Palep is a bariatric and upper GI surgeon with 17 years of experience. He specializes in minimally invasive and robotic weight loss surgeries. Dr. Palep is one of the first surgeons in India trained in Banded Bypass, Banded Sleeve Gastrectomy, and Mini Gastric Bypass. He has also received advanced training in Robotic GI Surgery in Italy and the USA.
Dr. Palep’s bariatric practice is certified as a Center of Excellence by the International Excellence Foundation (IEF). His practice has a morbidity rate of just 1%, which matches global standards. More than 90% of his diabetic patients stop using insulin and oral medications after surgery. He has published many articles in international journals and is invited to speak at conferences around the world.
Dr. Holovyna Svitlana is a gastroenterologist and nutritionist with more than 23 years of experience. She is a member of the Association of Dietitians and Gastroenterologists of Ukraine. She also belongs to the European Association for the Study of the Liver (EASL) and the Association of Preventive and Anti-Age Medicine.
Dr. Holovyna diagnoses and treats gastrointestinal disorders, metabolic diseases, and nutrition-related issues. She uses an integrated and evidence-based approach. Her focus is on restoring digestive health, managing chronic conditions, and improving patient well-being with personalized diet and treatment plans.